Fresh air injection for combustion exhaust systems



W. M. DEAN Oct. 16, 1962 FRESH AIR INJECTION FOR COMBUSTION EXHAUSTSYSTEMS Filed June 8, 1961 William M. Dean IN VEN TOR.

3,058,299 FRESBH AR INJECTION FER COWUSTION EXHAUST YSTEMS William M.Dean, R0. Box 636, Tuolumne, Calif. Filed June 8, 1961, Ser. No. 115,8064 Claims. (Cl. 60-30) This invention relates to a novel and useful freshair injection attachment for the exhaust pipe of a combustion engine andis specifically adapted to inject fresh air under pressure into theexhaust pipe of a combustion engine whereby the unburned fuel particlesand carbon particles may be more completely burned.

The fresh air injection attachment is adapted for securement to theexhaust pipe of a combustion engine adjacent the exhaust manifoldthereof whereby fresh air injected into the exhaust pipe may be mixedwith the exhaust gases in order that the unburned material beingexhausted may be more completely burned. The injection of fresh air intoan exhaust system enables unburned fuel particles to completely burnbefore egressing from the exhaust pipe and unburned carbon particlesbeing exhausted are also more completely burned. In this manner, theunburned particles normally exhausted from a combustion engine aregreatly reduced and therefore less of these unburned particles areexhausted into the atmosphere and form nuclei for small water dropletswhich is a major cause of smog.

The main object of this invention is to provide a novel means forreducing the tendency of combustion engine exhaust gases from formingsmog.

A further object of this invention, in accordance with the immediatelypreceding object, is to provide a fresh air injection attachment for theexhaust pipe of a combustion engine which will be capable of introducingfresh air under pressure into the exhaust pipe of the combustion enginewithout increasing or decreasing the back pressure in the exhaust pipethereby enabling the air injection attachment to be used in conjunctionwith a combustion engine without necessitating that adjustments and/orrevisions be made to the combustion engine in order to maintain itsmaximum efficiency.

Still another object of this invention is to provide an air injectionattachment including a blower assembly provided with means adapted to bedrivingly connected to an output shaft of the combustion engine withwhich it is associated.

Yet another object of this invention is to provide a fresh air injectionattachment in accordance with the preceding objects which will notnecessitate the removal of the conventional thermostatically controlledexhaust damper which is provided on substantially all vehicle internalcombustion engines to assist in warming up the internal combustionengine rapidly by increasing the back pressure in the exhaust manifoldduring the warmup period.

A further object of this invention is to provide a fresh air injectionattachment which may be readily incorporated into existing exhaustsystems.

A final object to be specifically enumerated herein is to provide afresh air injection attachment for the exhaust pipe of a combustionengine in accordance with the preceding objects which will conform toconventional forms of manufacture, be of simple construction and easy toinstall so as to provide a device that will be economically feasible,long lasting and readily adaptable to existing motor vehicle internalcombustion engines.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accom- 3,58,Z9 Patented Oct. 16, 1962 ice panyingdrawings forming a part hereof, wherein like numerals refer to likeparts throughout, and in which:

FIGURE 1 is a fragmentary top plan view of an internal combustion enginewith the fresh air injection at tachment of the instant inventionsecured to the exhaust pipe of the combustion engine and drivinglyconnected to an output shaft of the combustion engine, parts of thefresh air injection attachment being broken away and shown in section;

FIGURE 2 is a fragmentary side elevational view of the embodimentillustrated in FIGURE 1, parts of the attachment being broken away andshown in section;

FIGURE 3 is an enlarged fragmentary vertical sectional view takensubstantially upon the plane indicated by the section line 33 of FIGURE1;

FIGURE 4 is an enlarged horizontal sectional view taken substantiallyupon the plane indicated by the section line 4-4 of FIGURE 3.

Referring now more specifically to the drawings, the numeral it)generally designates an internal combustion engine which is providedwith an exhaust manifold generally referred to by the reference numeral12 and an output shaft 14.

The exhaust manifold 12, includes an outlet neck 16 and the fresh airinjection attachment of the instant invention is generally designated bythe reference numeral 18 and is mounted alongside the engine 12 by meansof suitable brackets 20 and 22. Additional brackets such as bracket 24-may also be provided if desired.

The attachment 18 includes a blower assembly generally referred to bythe reference numeral 26 which includes a blower rotor 28 rotatablymounted in a blower housing 3-0 which is provided with an air inlet 32.The housing 30 includes an air outlet 34 and an outlet nozzle 36. Therotor 28 is drivingly connected to an input shaft 38 by means of bevelgears 40 and 42 which are disposed in a transmission housing 44 securedto the blower housing 30 and the input shaft 38 is provided with apulley 46 which is drivingly connected to a pulley 48 carried by theoutput shaft 14 by means of an endless flexible belt 50. Accordingly,upon rotation of the output shaft 14, the blower rotor 28 will berotated at high speed in order to draw fresh air through the air inlet32 and exhaust the fresh air under pressure through the air outlet 34and into the outlet neck 36.

The internal combustion engine 10 has an exhaust pipe 52 normallyconnected to the outlet neck 16 of the exhaust manifold 12 but theattachment 18 includes a T fitting generally referred to by thereference numeral 54 which is disposed between the inlet end of theexhaust pipe 52 and the outlet end of the outlet neck 16. The outletneck 36 is secured to the horizontal leg 56 of the T-fitting 54 and itmay be observed from FIGURE 3 of the drawings that the attachment 18also includes an L- shaped outlet conduit generally referred to by thereference numeral 58. The short horizontal leg 60 of the outlet conduit58 is provided with a radial flange clampingly engaged between theconfronting radial flanges 64 and 66 of the outlet neck 36 and thehorizontal leg 56 of the T-fitting 54, and the vertical longer leg 68 ofthe out let conduit 58 extends longitudinally of the lower end of theT-fitting 54- and the inlet end of the exhaust pipe 52. The free end ofthe vertical leg 63 is open as at 79 and the vertical leg 68 of theoutlet conduit 58 is provided with a plurality of radial openings 72which are circumferentially spaced about the vertical leg 68 and arespaced longitudinally thereof.

The outlet neck 36 also includes a gate valve member 74 which comprisesa check valve and is swingably mounted as at 76 within the outlet neck36 for movement about an axis extending transversely of the outlet neck36. A

lever arm 78 is connected to the gate valve member 74 and is normallyurged toward a position closing the gate valve member 74 by means of anexpansion spring 80 whose opposite ends are secured between the free endof the lever 78 and the outlet neck 36. When the gate valve member 74 isswung to the closed position, it is extending transversely of the outletneck 36.

In operation, as the internal combustion engine It} is operated, theoutput shaft 14 rotates which in turn rotates the rotor 28. Air ispulled in through the air inlet 32 and is exhausted through the outletneck 36. Some of the air discharged through the outlet neck 36 continuescompletely through the outlet conduit 58 and egresses from the free endof the vertical leg 68 thereof as at 70. However, portions of the freshair under pressure within the outlet conduit 58 egress through theopenings 72. By discharging some of the fresh air under pressure throughthe openings 72, the jet efiect of portions of the fresh air beingdischarged from the open end of the vertical leg 68 which would have atendency to reduce the back pressure within the exhaust manifold 12 isoffset. Accordingly, although large quantities of fresh air are injectedinto the exahust pipe 52 under pressure, the back pressure within theexhaust manifold 12 is maintained substantially constant at all timesrelative to the normal back pressure within the exhaust manifold 12.

The diameter of the outlet conduit 53 and thus the obstruction effectedin the exhaust pipe 52 caused there by, the capacity of the blowerassembly 26 and the diameter of the openings 72 will be predeterminedfor a given internal combustion engine.

Thus it may be seen that the attachment 1% will deliver large quantitiesof fresh air under pressure to the exhaust pipe 52 in a manner wherebythe normal back pressure of the exhaust gases in the exhaust manifold12. is unaltered. The check valve defined by the gate valve member 74 isutilized to prevent higher pressure exhaust gases within the exhaustpipe 52 from backing up through the outlet conduit 58 and into theblower assembly 26 when the engine is operating under heavy loads atslow speed.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention asclaimed.

What is claimed as new is as follows:

1. In combination, a combustion engine having an exhaust manifoldattached to an end of an exhaust pipe by a T-fitting and an enginecooling fan connected to a power driven output shaft, an attachment forinjecting fresh air under pressure into said exhaust pipe Withoutincreasing or decreasing the back pressure of exhaust gases in saidexhaust pipe, said attachment comprising a blower having an input shaftdrivingly connected by a belt to said fan output shaft, an air inletextending horizontally and connected to one side of said T-fitting andto said blower, an air outlet conduit connected to said air inlet, saidair outlet conduit including a free end portion disposed within saidT-fitting and the upper end of said exhaust pipe directly adjacent saidmanifold, said outlet conduit extending longitudinally thereofdownwardly in said exhaust pipe away from said manifold in the directionof movement of exhaust gases through said exhaust pipe and in spacedrelation relative to the internal surfaces of said exhaust pipe, thefree terminal end of said outlet conduit being open and said free endportion including passage means for discharging some of the compressedair discharged through said outlet conduit radially and outwardly ofsaid free end portion whereby large amounts of fresh air under pressuremay be introduced by said blower into said exhaust pipe withoutincreasing or decreasing the back pressure in said exhaust pipe.

2. In the combination of claim 1 a valve in said air inlet, said valveincluding a gate valve member swingably mounted at one edge for movementabout an axis extending transversely of said air inlet and between aclosed position extending transversely of said air inlet conduit and anopen position with the free edge of said gate valve member extendingtoward said T-fitting, spring means yieldably urging said gate valvemember toward said closed position.

3. The combination of claim 1 wherein said discharging means comprises aplurality of circumferentially and axially spaced openings formed insaid free end portion, a check valve disposed in said air outlet conduitfor preventing reverse flow of gases therethrough from said exhaust pipeand into said blower, said valve including a gate valve member swingablymounted at one edge for movement about an axis extending transversely ofsaid outlet conduit and between a closed position extending transverselyof said outlet conduit and an open position with the free edge of saidgate valve member extending toward said T-fitting, spring meansyieldably urging said gate valve member toward said closed position.

4. In combination, an internal combustion engine, a horizontallyextending manifold connected to one side of the engine and an exhaustpipe, a T-fitting comprising a vertical tube having open ends and ahorizontal tube having one open end and another end connected to saidvertical tube between its ends, the upper end of said vertical tubeconnected to the center of said manifold, the lower end of said verticaltube connected to a vertically extending end portion of the exhaustpipe, an air blower operatively connected to and driven by said engine,an air supply conduit connecting the outlet of said blower to the openend of said horizontal tube, an L-shaped air conduit comprising ahorizontal portion and a vertical portion connected at adjacent ends,the other ends of said portions being open, the open end of saidhorizontal portion being provided with an integral radially extendingannular flange clamped between the open end of said horizontal tube andone end of the air supply conduit, said horizontal portion extendingthrough said horizontal tube into said vertical tube, said verticalportion extending downwardly into the vertical end portion of theexhaust pipe and provided with a plurality of circumferentially andaxially spaced bores, annular spaces being provided between saidvertical portion and said vertical tube and said vertical end portion ofthe exhaust pipe.

References Cited in the file of this patent UNITED STATES PATENTS1,843,999 White Feb. 9, 1932 2,649,685 Cohen Aug. 25, 1953 FOREIGNPATENTS 435,780 Great Britain Sept. 27, 1935

